1. Field of the Invention
The present invention relates to a liquid ejection apparatus including (a) a recording head configured to form image dots and flushing dots on a recording medium by ejecting ink droplets onto the recording medium and (b) a treatment-liquid ejection head configured to eject droplets of the treatment liquid.
2. Description of the Related Art
In general, an ink-jet printer including an ink jet head configured to eject ink droplets from a plurality of liquid-ejection openings performs a preliminary ejection (i.e., flushing) for ejecting ink whose viscosity has been increased, in addition to a normal ejection for ejecting the ink droplets to form an image, in order to prevent clogging in the liquid-ejection openings which is caused by the ink solidified in or near the liquid-ejection openings. In a conventional printer, the preliminary ejection is performed in parallel with the image forming, and flushing dots are formed on the recording medium by the ink ejected upon the preliminary ejection. In this conventional printer, the ink droplets are ejected in the preliminary ejection onto a background or a black area of the image formed on the recording medium, thereby making the flushing dots inconspicuous.
Further, there is known another conventional ink jet printer configured to apply treatment liquid on a recording medium in order to prevent spreading of a dot formed by ink ejected on the recording medium and to sharpen the dot.